Create a 12-second top-down koi pond entirely in After Effects. Kohaku, Showa, and golden koi should glide through clear green water with natural swimming motion and flapping fins, weaving between lily pads and pink water lilies while petals drift on the surface. Add rippling caustics on the pond bed and soft sky reflections on top. No stock footage. Build the fish and plants from shape layers and procedural textures, and give me controls for swim speed, body wiggle, fish size, and number of fish so it works as a template.